8 replies to this topic

[_Z_]

I'm working on my GISP Certification (GIS Professional, it's mapping software related) and one thing I need to do is earn points in the Contributions to the Profession area. This includes writing articles in newsletters and publishing maps. Since i'm a member of an astro club, I figured it'd be easy to get articles and maps published, would be about something I like doing, and would be useful to those in the hobby and the public.

GIS uses data sets that are available and while I can create data from scratch, it's not that easy to create certain types of data so I do have some restrictions. These aren't simple maps you draw, the data involved has geospatial properties that allow for all kinds of fun spatial analysis to be done. It also means i'm a little limited in the data I can pull together in some regards.

I'm trying to think of map ideas that can be used by club members, by the public wanting to learn information about astronomy, or to show information about the club.

Ideas for useful maps:

Local and State Light Pollution Maps

Observing Site Location Map vs Light Pollution Map - This may have mixed reactions. I wouldn't label the observing sites exact enough to be able to give them away (unless it's a public place like Cherry Springs State Park) but I could make a local map that shows all of the observing sites in Maryland club members use, giving club members and the public a rough idea of how close dark places to observe may be. This would be beneficial in showing the public that if they joined, there are dark skies closer than they think.

Star Party Maps - We could do a Maryland Map, Mid-Atlantic Region Map, East Coast Map, and even keep going and cover the other region of the US. A map that shows the entire US and all star parties may work but would need to be larger.

It would be very cool to map things in the sky, but I have absolutely no clue how that would be possible in ArcGIS at this time. All data I know of uses earth oriented coordinate systems, nothing involved in the sky, so i'm not sure if things could be projected correctly.

Any other ideas for maps that could be useful to a club or to the public to explain something at an open house?

Thanks,
Jeremy

[teast]

Hi Jeremy:

I obtained my GISP Certification a couple of years ago so I am familiar with what you are attempting to do. Your idea for a light pollution map is an excellent idea in my opinion. One variation that might be really interesting is to compare historical observations to current ones in areas where street lights have been turned off. You might also see if there is a corresponding increase or decrease in crime in these areas.

You can get great sets of historical data in shapefile format at the following two web sites:

http://www.globeatnight.org

http://www.starcount.org

You'll have to pick an area carefully to make sure you can identify areas where lights have been turned off but enough observations are available. I suggest looking in the Light Pollution forum for links to articles about cities turning out streetlights. PM me if you have questions and good luck on whatever you choose to do.

-Tom

[_Z_]

Tom, that's exactly the kind of stuff I was looking for!

A club member suggested working with the globe at night program and I didn't realize they actually had shapefiles! That makes things so much easier on my end.

[_Z_]

Well overlaying the Globe at Night star count data vs the Light Pollution Map shows some people must be crazy, there's a few mag 7 observations right in the middle of terrible light pollution. The results are generally pretty good and suggest that the skies aren't quite as bad as the map suggests.

I need to find the revised Light Pollution Map as a .tif though, that would be more useful.

[teast]

Not to go off topic, but I'd also like to encourage you to participate in the GLOBE at Night campaigns. There are four this year, the first from January 14-23. See the GLOBE at Night web site for further details:

http://www.globeatnight.org

You are now returned to your regular programming -

-Tom

[_Z_]

With data from 2006 up through every year it's definitely starting to produce some useful information, despite errors with the occasional report. I'll have to give it a shot this time around.

[George N]

Well overlaying the Globe at Night star count data vs the Light Pollution Map shows some people must be crazy, there's a few mag 7 observations right in the middle of terrible light pollution. The results are generally pretty good and suggest that the skies aren't quite as bad as the map suggests.

I need to find the revised Light Pollution Map as a .tif though, that would be more useful.

Globe at Night seems to be primarily aimed at kids, and I’ve just assumed that some of the kids don’t understand the magnitude scale, or had problems with the website's interface.

BTW, NASA’s Night Sky Network gave some astro clubs free Sky Quality Meters in order to take part in Globe At Night (one being my club). Globe at Night encourages the use of an SQM if you have one for data entry.

The SQM website also has a very extensive database of sky darkness readings submitted by their owners. See web page

[_Z_]

That SQM data sounds very promising! I'll have to download it and see how many people have been posting their results.

[Matthew Ota]

Night Sky Finder uses information from the World Atlas of Night Sky Brightness for the United States region. The Bortle Light Pollution scale uses the same color coding. You can screen capture your area by using Night Sky Finder to show your location's amount of light pollution.

Dark Sky Finder (USA only)

The World Atlas of the Artificial Night Sky Brigtness

The Bortle Light Pollution Scale

I hope these links help. You will also need bitmap (raster) graphic editing software like GIMP or PhotoShop. You can screen capture the map by pressing Ctrl PrtScrn and then pressing Ctrl-V after you open your graphics editor.